AASHTO TP 114:2016 Standard Method of Test for Determining the Interlayer Shear Strength (ISS) of Asphalt Pavement Layers.
8.1. Test specimens may be either Ia oralory-wnipacted I IMA or sampled from IIMA pavements.
8.2. Samples Cored from A.sphali Paveme,,i:
8.2.1. Mark the direction of traffic on the roadway surface before coring so that it can be identified once the core is removed.
8.2.2. Cores shall be taken full depth so that no prying action is needed to extract the cores from the pavement. (‘are shall be taken to avoid stress or damage to the interface during coring, handling. and transportation. If a core dcbonds at thc intcrfacc of interest during thc coring opcration. acquire additional core and make note of it on the coring report.
8.2.3. Label core specimens with a paint pen.
8.2.4. Roadway core specimens shall be approximately 150mm (6 in.) in diameter ith all surfaces of the perimeter perpendicular to the surface of the core within 6 mm (1/4 in.). If the height of the core above or below the interface being tested is greater than 50 mm (2 in.), it shall be trimmed with a wet masonry saw to a height of approximately 50 mm (2 in).
8.2.5. Mark the location of the interface layer with white or silver paint.
8.3. Lahoraiwi’-Compacied 4 cphali Miriure Samples:
8.3.1. The laboratory sample consists of two layers, top and bottom, with a tack coat at the interface of these layers. The diameter of each layer is 150 mm (6 in.). Compact the bottom layer of the sample to a height of 50mm (2 in.) and an air void content of 6.0 ± 1.0 percent using the Superpave according to T 312. The amount of tack coat to be applied is determined by the desired application rate. Utilize a laboratory scale to ensure that the correct amount of tack coat is applied. Heat the tack coat material to the specified application temperature, and apply it to the surface of the bottom layer at the specified application rate using a I -in. natural bristle brush. Allow the tack coat material to cure. Reheat the SOC mold, and place the compacted bottom layer in the mold. Place loose mix on top of the tack-coated bottom layer, and compact the top layer to a height of 50 mm (2 in.) and an air void content of 6.0 ± 1.0 percent using the SOC according to T 312.
8.4. Measure the diameter of the specimen and the thickness of both layers to the nearest 1 mm (0.04 in.).
8.5. Number of Te.ci Specinia’n.c—A single test shall consist of at least three specimens.AASHTO TP 114 pdf download.